I'm sorry, but for now ATUM doesn't send stock emails of the BOM. This feature is in our TO DO list.
Also, the emails are sent for all the products that are associated to that BOM, because actually they are low stock. It's in or TO DO trying to improve this behavior.
But I apologize as there is not ETA fot both features. However, we created a filter that can be used by our users, but it needs custom development skills.
The filter is 'atum/product_levels/prevent_notify_bom_parents' en "atum-product-levels/classes/Inc/Helpers.php" within the function "send_bom_stock_emails"
Hope this helps,